On-board diagnostics (OBD) refers to self-diagnostic and reporting capabilities of a vehicle. OBD systems include at least one engine control unit (ECU) in communication with a multitude of vehicle systems and subsystems. The OBD system provides a user with access to a status of the vehicle systems and subsystems, and may be used to read error codes of the various systems as well as to control or test the various systems and subsystems.
In order to access information of a vehicle's OBD system, a diagnostics tool connects to an OBD system of a vehicle, typically via a diagnostic connector port. The diagnostics tool can then communicate with the vehicle's OBD system, and read information associated with the various vehicle systems and subsystems. A diagnostics tool may also be operable to send instructions to the ECU of the vehicle which may route those instructions to actuators and sensors controlled by the ECU.
Diagnostics tools which can send instructions to an ECU are generally located in a vehicle workshop, as they are typically bulky and connected to a computer system that stores the commands locally and can generate the necessary commands according to the applicable communication protocol. Communication typically occurs as part of a communication session. Due to the relatively short-range communication used in such workshops, the communication protocol used to communicate with ECU's is particularly suitable for low latency communication. Delays in communications may result in time-outs as the system may assume that a connection has been lost. Existing systems are therefore not suitable for use over a high latency network, as the high latency network may result in delays that exceed applicable time-outs.
Attempts have been made to provide diagnostic tools which communicate with remote servers over open communication networks such as the Internet. However, unless the remote network has a minimal latency, for example 10 milliseconds, timeout errors will likely result. Low latency may be difficult to achieve over networks such as the internet, particularly where a communicating server is located a long way from a vehicle to be monitored.
The preceding discussion of the background to the invention is intended only to facilitate an understanding of the present invention. It should be appreciated that the discussion is not an acknowledgment or admission that any of the material referred to was part of the common general knowledge in the art as at the priority date of the application.